JP7056174B2 - Laminated body and bag composed of the laminated body - Google Patents

Description

The present invention relates to a laminate and a bag composed of the laminate.

As a bag for accommodating fluid contents such as liquid and powder, a bag made of a flexible packaging material is used. The bag has a main body portion in which the contents are housed, and a spout port portion connected to the main body portion and through which a liquid passes when the contents are poured out from the bag. The shapes of the main body and the spout are defined by the seal formed by heat-sealing the flexible packaging material.

The laminate constituting the flexible packaging material includes a base material and a sealant layer laminated on the base material and melted by heat sealing. The layer structure of the laminate is determined, for example, from the viewpoint of mechanical strength. For example, in Patent Document 1, the outer surface of the laminate is made of nylon, and the inner surface of the laminate is made of polyethylene. Nylon contributes to improving the mechanical strength of the laminate, such as puncture resistance.

Japanese Unexamined Patent Publication No. 10-218204

In the bag manufacturing process, the inner surfaces of the laminate are heat-sealed so that a part of the outer edge of the bag remains as an opening. The bag is then filled with the contents through the opening. The opening is then sealed with a heat seal. In this way, a bag containing the contents can be obtained. Such a bag manufacturing process may include a process in which a frictional force is generated on the outer surface of the bag. For example, there is a step of pulling out one bag from a plurality of stacked bags, a step of sliding a bag containing contents on a transport path, and the like. In order to carry out these steps efficiently, it is preferable that the coefficient of friction on the outer surface of the bag is small.

By the way, nylon has hygroscopicity. Therefore, when the outer surface of the laminate, that is, the outer surface of the bag is made of nylon, the friction coefficient of the outer surface of the bag increases due to the nylon absorbing moisture in the surrounding atmosphere. As a result, the frictional force generated on the outer surface of the bag becomes large, and it is considered that a part of the bag manufacturing process is hindered.

An object of the present invention is to provide a laminate capable of effectively solving such a problem.

The present invention is a laminate including an outer surface and an inner surface, and is located between the first base material constituting the outer surface, the sealant layer constituting the inner surface, and the first base material and the sealant layer. The first base material contains 51% by mass or more of polyethylene terephthalate or 51% by mass or more of polybutylene terephthalate, and the first base material contains 51% by mass or more of polyethylene terephthalate. In the case, the second base material is a laminated body containing 51% by mass or more of polybutylene terephthalate.

The laminate according to the present invention may further include a thin-film deposition layer located at least between the first base material and the second base material or between the second base material and the sealant layer. .. In this case, the laminate may further include a gas barrier coating film located on the vapor-filmed layer.

The laminate according to the present invention may further include a printing layer located between the first base material and the second base material.

In the laminate according to the present invention, the sealant layer may contain linear low-density polyethylene.

The piercing strength of the laminate according to the present invention is preferably 13N or more.

Two laminates according to the present invention are prepared and stored in a high temperature constant temperature bath at a temperature of 40 ° C. and a humidity of 90% for 48 hours, and then measured with respect to the outer surface of one of the laminates and the outer surface of the other laminate. The static friction coefficient and the dynamic friction coefficient are preferably 0.24 or less.

Two laminates according to the present invention are prepared and stored in an environment of a temperature of 20 to 30 ° C. and a humidity of 40 to 60% for at least 24 hours, and then measured after the outer surface of one of the laminates and the other of the laminates. The coefficient of static friction and the coefficient of dynamic friction with respect to the outer surface of the surface are called the coefficient of static friction at room temperature and the coefficient of dynamic friction at room temperature.
After measuring the room temperature static friction coefficient and the room temperature dynamic friction coefficient, the two layers are stored in a high temperature constant temperature bath at a temperature of 40 ° C. and a humidity of 90% for 48 hours, and then measured on the outer surface of one of the layers and on the other side. When the static friction coefficient and the dynamic friction coefficient with respect to the outer surface of the laminated body are referred to as a high temperature and high humidity static friction coefficient and a high temperature and high humidity dynamic friction coefficient,
Preferably, the value obtained by subtracting the normal temperature static friction coefficient from the high temperature and high humidity static friction coefficient is 0.03 or less, and the value obtained by subtracting the normal temperature dynamic friction coefficient from the high temperature and high humidity dynamic friction coefficient is 0.03 or less. ..

In the laminated body according to the present invention, the base material containing polybutyre terephthalate among the first base material and the second base material may have a multilayer structure portion including 10 or more layers.

In the laminate according to the present invention, the base material containing polybutyre terephthalate among the first base material and the second base material has a single-layer structure, and the IV value of polybutyre terephthalate is 1. It may be 10 dl / g or more and 1.35 dl / g or less.

In the laminate according to the present invention, the first base material may contain polybutylene terephthalate, and the second base material may contain polyethylene terephthalate.

In the laminate according to the present invention, the first base material may contain polyethylene terephthalate, and the second base material may contain polybutylene terephthalate.

The present invention is a bag having a main body portion and a spout portion connected to the main body portion, and includes a laminated body including an outer surface and an inner surface, and a sealing portion for joining the inner surfaces of the laminated body to each other. The laminate includes a first base material constituting the outer surface, a sealant layer constituting the inner surface, and a second base material located between the first base material and the sealant layer, and the first base material is provided. One base material contains 51% by mass or more of polyethylene terephthalate or 51% by mass or more of polybutylene terephthalate, and when the first base material contains 51% by mass or more of polyethylene terephthalate, the second base material contains 51% by mass. A bag containing% or more of polybutylene terephthalate.

According to the present invention, it is possible to provide a laminate having piercing resistance and slipperiness.

It is a front view which shows the bag in embodiment of this invention. It is sectional drawing which shows an example of the layer structure of the laminated body which constitutes a bag. It is sectional drawing which shows the other example of the layer structure of the laminated body which constitutes a bag. It is sectional drawing which shows an example of the layer structure of the 1st film of a laminated body. It is a figure which shows an example of the measuring method of a piercing strength. It is a figure which shows the measurement result of the friction coefficient of Examples A1 to A3 and Comparative Example A1. It is a figure which shows the layer structure and the evaluation result of Examples A1 to A3 and Comparative Example A1. It is a front view which shows the bag produced in Examples B1 to B7. It is a figure which shows the result of the normal temperature drop evaluation and the low temperature drop evaluation of Examples B1 to B7 when the bag of the first capacity is used. It is a figure which shows the result of the normal temperature drop evaluation and the low temperature drop evaluation of Examples B1 to B7 when the bag of the 2nd capacity was used. It is a figure which shows an example of the result of having analyzed the transparent vapor deposition layer formed on the substrate by the time-of-flight type secondary ion mass spectrometer.

An embodiment of the present invention will be described with reference to FIGS. 1 to 4. In the drawings attached to the present specification, the scale, aspect ratio, etc. are appropriately changed from those of the actual product and exaggerated for the convenience of illustration and comprehension.

In addition, the terms such as "parallel", "orthogonal", and "identical" and the values of length and angle, etc., which specify the shape and geometric conditions and their degrees as used in the present specification, are strictly referred to. Without being bound by the meaning, we will interpret it including the range where similar functions can be expected.

Bag FIG. 1 is a front view showing a bag 10 according to the present embodiment. The bag 10 is configured to contain fluid contents such as liquids and powders that can be refilled into bottles. Note that FIG. 1 shows a bag 10 in a state before the contents are filled (a state in which the contents are not contained). As the liquid contained in the bag 10, various liquids such as liquid detergents and shampoos can be considered.

In the present embodiment, the bag 10 is a gusset-type bag configured to be self-supporting. The bag 10 includes an upper portion 11, a lower portion 12, and a side portion 13, and has a substantially rectangular contour in the front view. The names such as "upper part", "lower part" and "side part", and the terms "upper side" and "lower part" are based on the state in which the bag 10 stands on its own with the gusset part down. It is merely a relative representation of the position and direction of 10 and its components. The posture during transportation and use of the bag 10 is not limited by the names and terms in the present specification.

As shown in FIG. 1, the bag 10 includes a main body portion 17 in which the contents are housed, and a spout portion 20 connected to the main body portion 17. The spout portion 20 is a portion through which a liquid passes when the contents are taken out from the bag 10. The width of the spout portion 20 is narrower than the width of the main body portion 17. Therefore, the user can accurately determine the pouring direction of the contents poured from the bag 10 through the pouring outlet portion 20.

Hereinafter, a specific configuration of the bag 10 including the main body portion 17 and the spout portion 20 will be described. As shown in FIG. 1, the bag 10 includes a front surface film 14 constituting the front surface, a back surface film 15 constituting the back surface, and a lower film 16 constituting the lower portion 12. The lower film 16 is arranged between the front surface film 14 and the back surface film 15 in a state of being folded back at the folded-back portion 16f.

The terms "front surface film", "back surface film", and "lower film" described above are merely those in which each film is partitioned according to the positional relationship, and the method of providing the film when manufacturing the bag 10 is described. It is not limited by the above terms. For example, the bag 10 may be manufactured using one film in which the front surface film 14, the back surface film 15, and the lower film 16 are connected in series, or the bag 10 may be manufactured in one sheet in which the front surface film 14, the lower film 16 are connected in series. It may be manufactured using a total of two films, one film and one back surface film 15, and one front surface film 14, one back surface film 15, and one lower film 16 for a total of three films. It may be manufactured using.

The inner surfaces of the front surface film 14, the back surface film 15, and the lower film 16 are bonded to each other by a sealing portion. In the plan view of the bag 10 as shown in FIG. 1, the seal portion is hatched.

As shown in FIG. 1, the sealing portion has an outer edge sealing portion extending along the outer edge of the bag 10. The outer edge seal portion includes a lower seal portion 12a extending to the lower portion 12 and a pair of side seal portions 13a extending along the pair of side portions 13. Further, the seal portion includes a spout seal portion 20a that defines the spout portion 20. When the spout portion 20 is formed in the corner between the upper portion 11 and the side portion 13 of the bag 10 as shown in FIG. 1, the spout seal portion 20a is connected to the side sealing portion 13a. In the bag 10 in which the contents are not contained, as shown in FIG. 1, the upper portion 11 of the bag 10 is an opening 11b. After the contents are housed in the bag 10, the inner surface of the front surface film 14 and the inner surface of the back surface film 15 are joined at the upper portion 11 to form an upper sealing portion and seal the bag 10.

The side seal portion 13a, the spout seal portion 20a, and the upper seal portion described later are seal portions formed by joining the inner surface of the front surface film 14 and the inner surface of the back surface film 15. On the other hand, the lower sealing portion 12a is formed by joining a sealing portion formed by joining the inner surface of the front surface film 14 and the inner surface of the lower film 16, and joining the inner surface of the back surface film 15 and the inner surface of the lower film 16. Includes a configured seal.

As long as the bags 10 can be sealed by joining the films facing each other, the method for forming the sealing portion is not particularly limited. For example, the inner surface of the film may be melted by heating and the inner surfaces may be welded to each other, that is, the seal portion may be formed by heat sealing. Alternatively, the sealing portion may be formed by adhering the inner surfaces of the opposing films to each other using an adhesive or the like.

Easy-to-open means The front surface film 14 and the back surface film 15 may be provided with the easy-to-open means 25 for tearing the front surface film 14 and the back surface film 15 to open the spout portion 20. For example, as shown in FIG. 1, the easy-to-open means 25 may include a notch 26 formed in the spout sealing portion 20a of the spout portion 20 and serving as a starting point of tearing. Further, a half-cut wire formed by laser processing, a cutter, or the like may be provided as an easy-to-open means 25 in a portion serving as a path for tearing the spout portion 20.

Although not shown, the easy-to-open means 25 may include a notch or a group of scars formed in the region of the front surface film 14 and the back surface film 15 where the spout seal portion 20a is formed. The scar group may include, for example, a plurality of through holes formed so as to penetrate the front surface film 14 and / or the back surface film 15. Alternatively, the scar group may include a plurality of holes formed on the outer surface of the front surface film 14 and / or the back surface film 15 so as not to penetrate the front surface film 14 and / or the back surface film 15.

Layer structure of front surface film and back surface film Next, the layer structure of the front surface film 14 and the back surface film 15 will be described. FIG. 2 is a cross-sectional view showing an example of a laminate 30 constituting the front surface film 14 and the back surface film 15. Further, FIG. 3 is a cross-sectional view showing another example of the laminate 30 constituting the front surface film 14 and the back surface film 15.

As shown in FIG. 2, the laminate 30 includes at least the first film 40, the second film 50, and the third film 60 in this order. The first film 40 is located on the outer surface 30y side, and the third film 60 is located on the inner surface 30x side opposite to the outer surface 30y. The inner surface 30x is a surface located on the content side.

The first film 40 includes at least the first base material 41. Further, as shown in FIGS. 2 and 3, the first film 40 may further include a print layer 42 located between the first base material 41 and the second base material 51. For example, the first film 40 may further include a print layer 42 provided on the first base material 41. The second film 50 includes at least the second base material 51. Further, as shown in FIGS. 2 and 3, the second film 50 may further include a thin-film deposition layer 52 provided on the second base material 51. In the example shown in FIG. 2, the vapor deposition layer 52 is provided on the outer surface 30y side of the second base material 51. Further, in the example shown in FIG. 3, the vapor deposition layer 52 is provided on the inner surface 30x side of the second base material 51. The third film 60 includes at least the sealant layer 61.

The first film 40 and the second film 50 are bonded by the first adhesive layer 45, and the second film 50 and the third film 60 are bonded by the second adhesive layer 55. Therefore, the laminated body 30 shown in FIG. 2 is sequentially arranged from the outer surface side to the inner surface side.
1st base material / printing layer / 1st adhesive layer / vapor deposition layer / 2nd base material / 2nd adhesive layer / sealant layer,
It can be said that it has. Further, the laminated body 30 shown in FIG. 3 is sequentially arranged from the outer surface side to the inner surface side.
1st base material / printing layer / 1st adhesive layer / 2nd base material / thin film deposition layer / 2nd adhesive layer / sealant layer,
It can be said that it has. As described above, the thin-film deposition layer 52 may be located between the first base material 41 and the second base material 51, or may be located between the second base material 51 and the sealant layer 61. .. In addition, "/" represents the boundary between layers.

Hereinafter, the first film 40, the first adhesive layer 45, the second film 50, the second adhesive layer 55, and the third film 60 will be described in detail.

(1st film)
In the example shown in FIGS. 2 and 3, the first film 40 includes a first base material 41 constituting the outer surface 30y of the laminated body 30, a printing layer 42 provided on the inner surface 30x side of the first base material 41, and the like. including.

[Print layer]
The printed layer 42 is a layer printed on the first base material 41 in order to show product information or give an aesthetic impression to the bag 10. The print layer 42 represents characters, numbers, symbols, figures, patterns, and the like. As the material constituting the print layer 42, an ink for gravure printing or an ink for flexographic printing can be used. As a specific example of the ink for gravure printing, a finale manufactured by DIC Graphics Co., Ltd. can be mentioned.

[First base material]
The first base material 41 contains polybutylene terephthalate (hereinafter, also referred to as PBT) as a main component. For example, the first base material 41 contains 51% by mass or more of PBT. Hereinafter, the advantage that the first base material 41 contains PBT will be described.

PBT has excellent dimensional stability and therefore excellent printability. Therefore, as in the case of polyethylene terephthalate (hereinafter, also referred to as PET), the print layer 42 can be provided on the first base material 41 containing PBT.

In addition, PBT has high strength. Therefore, the bag 10 can be made piercing resistant, as in the case where the laminate 30 constituting the bag 10 contains nylon.

Further, PBT has a characteristic that it is less likely to absorb water than nylon. Therefore, it is possible to prevent the first base material 41 from absorbing moisture and reducing the laminating strength of the laminated body 30 and increasing the friction coefficient of the outer surface 30y of the first film 40.

Hereinafter, the configuration of the first base material 41 including PBT will be described in detail. As the configuration of the first base material 41 containing PBT in the present embodiment, either the following first configuration or the second configuration may be adopted.

[First composition of the base material]
The content of PBT in the first base material 41 according to the first configuration is preferably 51% by mass or more, more preferably 60% by mass or more, further preferably 70% by mass or more, and particularly preferably 75% by mass or more. It is preferably 80% by mass or more. By setting the PBT content to 51% by mass or more, the first film 40 can be provided with excellent impact strength and pinhole resistance.

The PBT used as a main component preferably contains terephthalic acid in an amount of 90 mol% or more, more preferably 95 mol% or more, still more preferably 98 mol% or more, and most preferably 100 as a dicarboxylic acid component. It is mol%. The glycol component is preferably 90 mol% or more, more preferably 95 mol% or more, still more preferably 97 mol% or more, and most preferably 1,4-butanediol at the time of polymerization. It does not contain anything other than by-products produced by the ether bond of butanediol.

The first base material 41 may contain a polyester resin other than PBT. Thereby, for example, it is possible to adjust the film forming property and the mechanical properties of the first base material 41 when the film-shaped first base material 41 is biaxially stretched.
Examples of polyester resins other than PBT include polyester resins such as PET, polyethylene naphthalate (PEN), polybutylene naphthalate (PBN), and polypropylene terephthalate (PPT), as well as isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, and biphenyldicarboxylic acid. , Cyclohexanedicarboxylic acid, adipic acid, azelaic acid, PBT resin copolymerized with dicarboxylic acids such as sebacic acid, ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, neopentyl glycol, 1,5 -PBT resin in which diol components such as pentanediol, 1,6-hexanediol, diethylene glycol, cyclohexanediol, polyethylene glycol, polytetramethylene glycol, and polycarbonate diol are copolymerized can be mentioned.

The amount of the polyester resin other than PBT added is preferably 49% by mass or less, more preferably 40% by mass or less. If the amount of the polyester resin other than PBT added exceeds 49% by mass, it is considered that the mechanical properties of PBT are impaired and the impact strength, pinhole resistance, and drawability are insufficient.

The first base material 41 may contain, as an additive, a polyester-based or polyamide-based elastomer in which at least one of a flexible polyether component, a polycarbonate component, and a polyester component is copolymerized. This makes it possible to improve the pinhole resistance at the time of bending. The amount of the additive added is, for example, 20% by mass. If the amount of the additive added exceeds 20% by mass, the effect as the additive may be saturated, the transparency of the first base material 41 may be lowered, and the like may occur.

An example of a method for producing the film-shaped first base material 41 according to the first configuration will be described. Here, a method for producing the film-shaped first base material 41 by the casting method will be described. More specifically, a method of casting a resin having the same composition in multiple layers at the time of casting will be described.

Since PBT has a high crystallization rate, crystallization proceeds even during casting. At this time, when cast in a single layer without multi-layering, the crystal grows to a large size because there is no barrier that can suppress the growth of the crystal, and the obtained unstretched raw fabric is obtained. Yield stress increases. Therefore, it is easy to break when the unstretched raw fabric is biaxially stretched. Further, it is considered that the yield stress of the obtained biaxially stretched film becomes high and the formability of the biaxially stretched film becomes insufficient.
On the other hand, if the same resin is multi-layered at the time of casting, the stretching stress of the unstretched sheet can be reduced. Therefore, stable biaxial stretching is possible, and the yield stress of the obtained biaxially stretched film is low. This makes it possible to obtain a film that is flexible and has high breaking strength.

FIG. 4 is a cross-sectional view showing an example of the layer structure of the first film. When the first base material 41 is produced by casting the resin in multiple layers, as shown in FIG. 4, the first base material 41 of the first film 40 is composed of a multilayer structure portion including a plurality of layers 41a. .. Each of the plurality of layers 41a may contain PBT as a main component. For example, each of the plurality of layers 41a preferably contains 51% by mass or more of PBT, and more preferably 60% by mass or more of PBT. In the plurality of layers 41a, the n + 1st layer 41a is directly laminated on the nth layer 41a. That is, no adhesive layer or adhesive layer is interposed between the plurality of layers 41a.

The reason why the characteristics of the PBT film are improved by the multi-layering is presumed as follows. When laminating resins, even if the composition of the resins is the same, there is an interface between the layers, and the interface accelerates crystallization. On the other hand, the growth of large crystals beyond the thickness of the layer is suppressed. Therefore, it is considered that the size of the crystal (spherulite) becomes smaller.

As a specific method for reducing the size of spherulites by multi-layering, a general multi-layering device (multi-layer feed block, static mixer, multi-layer multi-manifold, etc.) can be used. For example, a method of stacking thermoplastic resins fed from different flow paths using two or more extruders in multiple layers using a feed block, a static mixer, a multi-manifold die, or the like can be used. When the resins having the same composition are multi-layered, it is also possible to introduce the above-mentioned multi-layering device into the melt line from the extruder to the die by using only one extruder.

The first base material 41 is composed of a multilayer structure portion including at least 10 layers or more, preferably 60 layers or more, more preferably 250 layers or more, and further preferably 1000 or more layers 41a. By increasing the number of layers, the size of spherulites in PBT in the unstretched raw fabric state can be reduced, and subsequent biaxial stretching can be stably carried out. Further, the yield stress of PBT in the state of the biaxially stretched film can be reduced. Preferably, the diameter of the spherulites in PBT of the unstretched raw fabric is 500 nm or less.

The stretching temperature (hereinafter, also referred to as MD stretching temperature) in the longitudinal stretching direction (hereinafter, MD) when biaxially stretching the unstretched raw fabric of PBT to prepare a biaxially stretched film is preferably 40 ° C. or higher. Yes, more preferably 45 ° C. or higher. By setting the MD stretching temperature to 40 ° C. or higher, it is possible to prevent the film from breaking. The MD stretching temperature is preferably 100 ° C. or lower, more preferably 95 ° C. or lower. By setting the MD stretching temperature to 100 ° C. or lower, it is possible to suppress the phenomenon that the orientation of the biaxially stretched film does not occur.

The stretch ratio in MD (hereinafter, also referred to as MD stretch ratio) is preferably 2.5 times or more. This makes it possible to orient the biaxially stretched film and realize good mechanical properties and a uniform thickness. The MD stretch ratio is, for example, 5 times or less.

The stretching temperature (hereinafter, also referred to as TD stretching temperature) in the transverse stretching direction (hereinafter, also referred to as TD) is preferably 40 ° C. or higher. By setting the TD stretching temperature to 40 ° C. or higher, it is possible to prevent the film from breaking. The TD stretching temperature is preferably 100 ° C. or lower. By setting the TD stretching temperature to 100 ° C. or lower, it is possible to suppress the phenomenon that the orientation of the biaxially stretched film does not occur.

The stretch ratio in TD (hereinafter, also referred to as TD stretch ratio) is preferably 2.5 times or more. This makes it possible to orient the biaxially stretched film and realize good mechanical properties and a uniform thickness. The MD stretch ratio is, for example, 5 times or less.

The TD relaxation rate is preferably 0.5% or more. As a result, it is possible to prevent breakage from occurring during heat fixing of the biaxially stretched film of PBT. The TD relaxation rate is preferably 10% or less. As a result, it is possible to prevent the biaxially stretched film of PBT from sagging and causing thickness unevenness.

The thickness of the layer 41a of the first base material 41 shown in FIG. 4 is preferably 3 nm or more, and more preferably 10 nm or more. The thickness of the layer 41a is preferably 200 nm or less, more preferably 100 nm or less, and further preferably 75 nm or less.
The thickness of the first base material 41 is preferably 9 μm or more, more preferably 12 μm or more. The thickness of the first base material 41 is preferably 25 μm or less, more preferably 20 μm or less. By making the thickness of the first base material 41 9 μm or more, the first base material 41 has sufficient strength. Further, by reducing the thickness of the first base material 41 to 25 μm or less, the first base material 41 exhibits excellent moldability. Therefore, the step of processing the laminated body 30 including the first base material 41 to manufacture the bag 10 can be efficiently performed.

As described above, when the first base material 41 is composed of a multilayer structure portion including a plurality of layers 41a, a part of the plurality of layers 41a may contain a polyester resin other than PBT as a main component. For example, the first base material 41 may be composed of a plurality of layers 41a containing PBT as a main component and a layer 41a containing, for example, PET as a main component, located between the layers 41a of two PBTs. .. That is, the first base material 41 may be configured by alternately laminating the layer 41a containing PBT as a main component and, for example, the layer 41a containing PET as a main component.

[Second composition of the base material]
The first base material 41 according to the second configuration is made of a single-layer film containing polyester having butylene terephthalate as a main repeating unit. For example, the first base material 41 contains 1,4-butanediol as a glycol component or an ester-forming derivative thereof and terephthalic acid as a dibasic acid component or an ester-forming derivative thereof as main components. Includes homo or copolymer type polyesters obtained by condensation. The content of PBT in the first base material 41 according to the second configuration is preferably 51% by mass or more, more preferably 60% by mass or more, further preferably 70% by mass or more, and further preferably 80% by mass or more. Most preferably, it is 90% by mass or more. Further, it is preferable that the first base material 41 according to the second configuration is composed of only polybutylene terephthalate and an additive.

In order to impart mechanical strength to the first base material 41, PBT having a melting point of 200 ° C. or higher and 250 ° C. or lower and an IV value of 1.10 dl / g or higher and 1.35 dl / g or lower is preferable. .. Further, those having a melting point of 215 ° C. or higher and 225 ° C. or lower and an IV value of 1.15 dl / g or higher and 1.30 dl / g or lower are particularly preferable. These IV values may be satisfied by the entire material constituting the first base material 41. The IV value can be calculated based on JIS K 7376-5: 2000.

The first base material 41 according to the second configuration may contain a polyester resin other than PBT such as PET in a range of 30% by mass or less. When the first base material 41 contains PET in addition to PBT, PBT crystallization can be suppressed and the stretchability of the PBT film can be improved. As the PET to be blended in the PBT of the first base material 41, polyester having ethylene terephthalate as a main repeating unit can be used. For example, a homotype containing ethylene glycol as a glycol component and terephthalic acid as a diprotic acid component as main components can be preferably used. In order to impart good mechanical strength characteristics, PET having a melting point of 240 ° C. or higher and 265 ° C. or lower and an IV value of 0.55 dl / g or higher and 0.90 dl / g or lower is preferable. Further, those having a melting point of 245 ° C. or higher and 260 ° C. or lower and an IV value of 0.60 dl / g or higher and 0.80 dl / g or lower are particularly preferable.
By setting the blending amount of PET to 30% by mass or less, it is possible to prevent the unstretched raw fabric and the stretched film from becoming too rigid. As a result, the stretched film becomes brittle, and it is possible to prevent the stretched film from being lowered in pressure resistance, impact strength, piercing strength, and the like. In addition, it is possible to suppress the occurrence of stretching malfunction when stretching the unstretched raw fabric.

The first base material 41 is, if necessary, a lubricant, an antiblocking agent, an inorganic bulking agent, an antioxidant, an ultraviolet absorber, an antistatic agent, a flame retardant, a plasticizer, a colorant, a crystallization inhibitor, and crystallization. It may contain additives such as accelerators. Further, the polyester resin pellet used as the raw material of the first base material 41 has a water content of 0.05% by weight or less, preferably 0.01% by weight, before heating and melting in order to avoid a decrease in viscosity due to hydrolysis during heating and melting. It is preferable to use it after sufficiently pre-drying it so that it becomes% or less.

An example of a method for producing the film-shaped first base material 41 according to the second configuration will be described.

In order to stably produce the film of the first base material 41 having the above-mentioned structure, it is important to suppress the growth of crystals in the state of unstretched raw fabric. Specifically, when the extruded PBT-based melt is cooled to form a film, the crystallization temperature region of the polymer is cooled at a certain rate or higher, that is, the raw fabric cooling rate is an important factor. The raw fabric cooling rate is, for example, 200 ° C./sec or higher, preferably 250 ° C./sec or higher, and particularly preferably 350 ° C./sec or higher. Since the unstretched raw fabric formed at a high cooling rate maintains a low crystalline state, the stability of bubbles during stretching is improved. Furthermore, since film formation at high speed is possible, the productivity of the film is also improved. When the cooling rate is less than 200 ° C./sec, it is considered that the crystallinity of the obtained unstretched raw fabric becomes high and the stretchability decreases. Further, in an extreme case, it is possible that the stretching bubble bursts and stretching does not continue.

The unstretched raw fabric containing PBT as a main component is preferably transported to a space for biaxial stretching while keeping the atmospheric temperature at 25 ° C. or lower, preferably 20 ° C. or lower. As a result, the crystallinity of the unstretched raw fabric immediately after the film formation can be maintained even when the residence time is long.

The biaxial stretching method for stretching the unstretched raw fabric to obtain a stretched film is not particularly limited. For example, by the tubular method or the tenter method, the vertical direction and the horizontal direction may be stretched at the same time, or the vertical direction and the horizontal direction may be sequentially stretched. Of these, the tubular method is particularly preferably adopted because it is possible to obtain a stretched film having a good balance of physical properties in the circumferential direction.

In the tubular method, the unstretched raw fabric guided to the stretched space is inserted between a pair of low-speed nip rolls and then heated by a stretching heater while press-fitting air into the unstretched raw fabric. After the stretching is completed, air is blown onto the stretched film by a cooling shoulder air ring. The draw ratio is preferably 2.7 times or more and 4.5 times or less, respectively, for MD and TD in consideration of the stretch stability, the strength physical characteristics of the stretched film, the transparency, and the thickness uniformity. By setting the draw ratio to 2.7 times or more, the tensile elastic modulus and impact strength of the stretched film can be sufficiently secured. In addition, by setting the draw ratio to 4.5 times or less, it is possible to suppress the occurrence of excessive molecular chain strain due to stretching, and it is possible to suppress the occurrence of breakage and puncture during the stretching process, so that the stretched film is stable. Can be made into.

The stretching temperature is preferably 40 ° C. or higher and 80 ° C. or lower, and particularly preferably 45 ° C. or higher and 65 ° C. or lower. Since the unstretched raw fabric produced at the above-mentioned high cooling rate has low crystallinity, the unstretched raw fabric can be stably stretched even when the stretching temperature is relatively low. Further, by setting the stretching temperature to 80 ° C. or lower, it is possible to suppress the shaking of the stretching bubble and obtain a stretched film having good thickness accuracy. Further, by setting the stretching temperature to 40 ° C. or higher, it is possible to suppress the occurrence of excessive stretching orientation crystallization due to low temperature stretching and prevent whitening of the film.

The first base material 41 produced as described above is composed of, for example, a single layer containing polyester having butylene terephthalate as a main repeating unit. According to the above-mentioned production method, since the unstretched raw fabric is formed at a high cooling rate, a low crystalline state can be maintained even when the unstretched raw fabric is composed of a single layer. Therefore, the unstretched raw fabric can be stably stretched.

(First adhesive layer)
The first adhesive layer 45 contains a first adhesive for adhering the first film 40 and the second film 50. Examples of the first adhesive include an ether-based two-component reaction type adhesive, an ester-based two-component reaction type adhesive, and the like.

Examples of the ether-based two-component reaction type adhesive include polyether polyurethane and the like. The polyether polyurethane is a cured product produced by reacting a polyether polyol as a main agent with an isocyanate compound as a curing agent. Examples of the isocyanate compound include aromatic isocyanate compounds such as tolylene diisocyanate (TDI), 4,4'-diphenylmethane diisocyanate (MDI) and xylylene diisocyanate (XDI), hexamethylene diisocyanate (HDI) and isophorone diisocyanate (IPDI). The aliphatic isocyanate compound of the above, or an adduct or a multimer of the above-mentioned various isocyanate compounds can be used. Preferably, an aromatic isocyanate compound is used as the curing agent. This makes it possible to further increase the laminating strength between the first film 40 and the second film 50 as compared with the case of using an aliphatic isocyanate compound.

Examples of the ester-based two-component reaction type adhesive include polyester polyurethane and polyester. Polyester polyurethane is a cured product produced by the reaction of a polyester polyol as a main agent and an isocyanate compound as a curing agent. Examples of the isocyanate compound are the same as in the case of the above-mentioned ether-based adhesive.

In the first adhesive layer 45, for example, the adhesive composition is applied to the first film 40 or the second film 50, and then the adhesive composition is dried, and the main agent and the solvent in the adhesive composition are used. Is reacted to cure the adhesive composition. The thickness of the first adhesive layer 45 is preferably 1 μm or more, more preferably 2 μm or more.

(2nd film)
The second film 50 includes a second base material 51 and a thin-film deposition layer 52 provided on the second base material 51.

[Second base material]
The second base material 51 contains PET as a main component. For example, the second base material 51 contains 51% by mass or more of PET. Since the second base material 51 contains PET, the hygroscopicity of the second base material 51 is lower than that in the case where the second base material 51 contains nylon. This makes it possible to prevent the second base material 51 from expanding or deteriorating the characteristics of the second base material 51 due to the moisture contained in the contents. When the main component of the second base material 51 is PET, the content of PET in the second base material 51 may be 95% by mass or more.

The thickness of the second base material 51 is preferably 9 μm or more, more preferably 12 μm or more. The thickness of the second base material 51 is preferably 25 μm or less, more preferably 20 μm or less. By making the thickness of the second base material 51 9 μm or more, the second base material 51 has sufficient strength. Further, by reducing the thickness of the second base material 51 to 25 μm or less, the second base material 51 exhibits excellent moldability. Therefore, the step of processing the laminated body 30 to manufacture the bag 10 can be efficiently performed.

[Embedded layer]
The thin-film deposition layer 52 is a layer provided on the laminate 30 in order to enhance the gas barrier property of the laminate 30. Examples of the material constituting the vapor-deposited layer 52 include metals such as aluminum, metal oxides such as aluminum oxide, and inorganic oxides such as silicon oxide.

The thin-film deposition layer 52 functions as a layer having a gas barrier function of blocking the permeation of oxygen gas, water vapor, and the like. The vapor deposition layer 52 may be provided with two or more layers. When two or more thin-film deposition layers 52 are provided, they may have the same composition or different compositions. Examples of the method for forming the vapor deposition layer 52 include a physical vapor deposition method (PVD method) such as a vacuum vapor deposition method, a sputtering method, and an ion plating method, or a plasma chemical vapor deposition method and heat. Examples thereof include a chemical vapor deposition method, a chemical vapor deposition method such as a photochemical vapor deposition method, and a CVD method. Specifically, a thin-film deposition film film forming apparatus can be used to form a thin-film deposition layer on the film-forming roller.

The thin-film deposition layer 52 may be a transparent vapor-deposited layer formed of a transparent inorganic substance such as aluminum oxide (aluminum oxide) or silicon oxide. As the transparent thin-film deposition layer, it is preferable to use an amorphous thin film of aluminum oxide. Specifically, the transparent vapor deposition layer is a non-crystalline thin film of aluminum oxide represented by the formula AlO _X (wherein X represents a number in the range of 0.5 to 1.5). As the transparent vapor-deposited layer, a non-crystalline thin film of aluminum oxide in which the value of X decreases in the depth direction from the film surface toward the inner surface can be used. The amorphous thin film of aluminum oxide is represented by the formula AlO _X (where X represents a number in the range of 0.5 to 1.5), and is expressed in the depth direction from the surface of the thin film toward the inner surface. It is preferable that the value of X increases toward the end. As the value of X in the above formula, basically, a value of X = 0.5 or more can be used, but when X = less than 1.0, coloring is intense and transparent. Since it is inferior in properties, it is preferable to use one having X = 1.0 or more. Further, since the one with X = 1.5 is in a state where Al and oxygen are completely oxidized, the one with X = 1.5 can be used as the upper limit. When the value of X in the above formula is 0, it is a completely inorganic simple substance (pure substance) and is not transparent.

The rate of decrease in the value of X is determined in the depth direction by using a surface analyzer such as an X-ray photoelectron spectrometer (XPS) or a secondary ion mass spectrometer (SIMS). It can be confirmed by performing elemental analysis of the transparent vapor deposition layer by using a method of analysis such as ion etching.

<First Preferred Form of Transparent Vapor Deposition Layer>
Hereinafter, the first preferable form of the transparent thin-film deposition layer will be described. The transparent vapor deposition layer may be a layer composed of a mixture of inorganic compounds containing covalent bonds of aluminum atoms and carbon atoms. In this case, the transparent vapor deposition layer is a covalent bond of aluminum atom and carbon atom to the peak measured by ion etching in the depth direction using an X-ray photoelectron spectroscope (measurement conditions: X-ray source AlKα, X-ray output 120W). It may also have a gas barrier property that indicates the presence of the above-mentioned substance, has transparency, and hinders the permeation of oxygen, water vapor, and the like.

A covalent bond between a metal atom and a carbon atom may be formed at the interface between the transparent vapor-filmed layer and the second base material 51. For example, when the transparent thin-film deposition layer contains aluminum oxide, it can be assumed that a covalent bond between an aluminum atom and a carbon atom is formed at the interface between the second base material 51 and the transparent vapor-film deposition layer. Covalent bonds can be detected by measurement by X-ray photoelectron spectroscopy (hereinafter, abbreviated as "XPS measurement").

Further, in the transparent vapor-filmed layer, the abundance ratio of the covalent bond between the aluminum atom and the carbon atom is the total bond containing the carbon atom observed when the interface between the transparent vapor-filmed layer and the second base material 51 is measured by XPS measurement. Of the above, it is preferably in the range of 0.3% or more and 30% or less. As a result, the adhesion between the transparent thin-film deposition layer and the second base material 51 is enhanced, the transparency is excellent, and a well-balanced performance as a gas barrier vapor-film deposition film can be obtained.

If the abundance ratio of the covalent bond between the aluminum atom and the carbon atom is less than 0.3%, the improvement of the adhesion of the transparent vapor-filmed layer is insufficient, and it becomes difficult to stably maintain the barrier property.

Further, the AL (aluminum) / O (oxygen) ratio of the transparent vapor-filmed layer containing aluminum oxide as a main component is on the opposite side of the second base material 51 from the interface between the second base material 51 and the transparent vapor-filmed layer. It is preferably 1.0 or less in the range up to 3 nm toward the surface of the transparent thin-film deposition layer.
When the AL / O ratio exceeds 1.0 within the range from the interface between the transparent thin-film deposition layer and the second base material 51 toward the surface of the transparent vapor-filming layer on the opposite side of the second base material 51, the second base material 51 is second. The adhesion between the base material 51 and the transparent thin-film vapor deposition layer becomes insufficient, the proportion of aluminum increases, and the transparency of the transparent thin-film deposition layer decreases.

The thickness of the transparent thin-film deposition layer is, for example, 20 Å or more and 200 Å, preferably 30 Å or more and 150 Å. If it is less than 30 Å, the gas barrier property may be insufficient. On the other hand, if it exceeds 150 Å, the gas barrier performance of the laminated body 30 may not be maintained. The reason for this is not clear, but if the thickness of the transparent vapor-deposited layer exceeds 150 Å, the flexibility of the laminated body 30 decreases, and when the laminated body 30 is used for the bag 10, a part of the transparent vapor-filmed layer is cracked or pinholeed. Is considered to occur and the gas barrier property is lowered. The thickness of the transparent thin-film deposition layer is preferably 40 Å or more and 130 Å or less, and more preferably 50 Å or more and 120 Å or less. The thickness of the transparent thin-film deposition layer can be measured by a fundamental parameter method using, for example, a fluorescent X-ray analyzer (trade name: RIX2000 type, manufactured by Rigaku Co., Ltd.). Further, as a means for changing the thickness of the transparent thin-film vapor deposition layer, a method of changing the deposition rate of the transparent thin-film deposition layer, a method of changing the vapor deposition rate, or the like can be used.

When the transparent vapor deposition layer is formed on the inner surface 30x side of the second base material 51, the surface of the second base material 51 on the inner surface 30x side is subjected to pretreatment such as corona discharge treatment, frame treatment, and plasma treatment in advance. You may leave it. In particular, when a covalent bond between a metal atom and a carbon atom is formed at the interface between the transparent thin-film deposition layer and the second base material 51, the front with respect to the surface with the second base material 51 on which the transparent vapor-film deposition layer is to be formed. It is preferable to apply the treatment. When the pretreatment is plasma treatment, plasma is supplied to the surface with the second base material 51 in a reduced pressure environment of 0.1 Pa or more and 100 Pa or less by the pretreatment device. For plasma, an inert gas such as argon alone or a mixed gas of oxygen, nitrogen, carbon dioxide gas and one or more of them is used as a plasma raw material gas, and the plasma raw material gas is excited by a potential difference due to a high frequency voltage or the like. By doing so, it can be generated.

By the pretreatment, plasma can be confined in the vicinity of the surface of the second base material 51. Thereby, the shape of the surface of the second base material 51, the chemical bond state and the functional group can be changed, and the chemical properties of the surface of the second base material 51 can be changed. This makes it possible to improve the adhesion between the second base material 51 and the transparent thin-film deposition layer.

<Second Preferred Form of Transparent Vapor Deposition Layer>
Next, a second preferable form of the transparent thin-film deposition layer will be described. In addition, in this application, the transparent vapor-deposited layer may satisfy both the above-mentioned first preferable form and the second preferable form described below, or may satisfy only one of the forms. It is also conceivable that the transparent vapor deposition layer of the present application does not satisfy either of the above-mentioned first preferred form and the second preferred form described below.

In the transparent thin-film deposition layer, a transition region that defines the adhesion strength between the substrate such as the second substrate 51 and the transparent vapor-film deposition layer such as the aluminum oxide vapor-film deposition film may be formed in the transparent vapor-film deposition layer. When the transparent vapor deposition layer is an aluminum oxide vapor deposition film, the transition region is formed on aluminum hydroxide detected by etching the aluminum oxide vapor deposition film using the flight time type secondary ion mass spectrometry (TOF-SIMS). Includes a modified binding structure (Al2O4H). The transformation rate of the transition region defined by the ratio of the transformed transition region defined by using TOF-SIMS to the aluminum oxide vapor-deposited film defined by etching using TOF-SIMS is preferable. It is 45% or less. Such a form is based on the finding that by defining the transformation rate of the transition region, it is possible to specify the laminated body 30 having a barrier property with improved adhesion strength between the base material and the aluminum oxide vapor-deposited film. It is a thing.

The metamorphic rate of the transition region will be specifically described. First, etching is performed from the outermost surface of the aluminum oxide vapor-deposited film by Cs using a flight-time type secondary ion mass analyzer, and the elemental bond at the interface between the aluminum oxide vapor-deposited film and the plastic substrate and the elemental bond of the vapor-deposited film are formed. taking measurement. Subsequently, as shown in FIG. 11, each measured graph is obtained for the measured elements and element bonds.

In order to narrow the transition region of the interface between the plastic substrate formed by aluminum hydroxide and the vapor-deposited film in the aluminum oxide vapor-deposited film as much as possible, pay attention to _AL2O4H . _The position where the intensity becomes H1 in FIG. 11) is specified as the interface between the plastic substrate and the aluminum oxide vapor _- deposited film (the position where the horizontal axis (Cycle) is T1 in FIG. 11). Further, the area from the interface to the surface of the aluminum oxide vapor-deposited film (the position where the horizontal axis (Cycle) is T ₀ in FIG. 11) is specified as the aluminum oxide-deposited film. Subsequently, 2) the peak in the graph representing the elemental bond AL2O4H (the position where the horizontal axis (Cycle) is T ₂ in FIG. 11) is obtained, and the position from the peak position to the interface position is specified as a transition region. Subsequently, 3) (transition region from the peak of the element-bonded AL2O4H to the interface / aluminum oxide vapor-deposited film) × 100 (%) is used to determine the transformation rate of the transition region to aluminum hydroxide. In the example shown in FIG. 11, the metamorphism rate is (W2 / W1) × 100 (%).

In the film formation of the aluminum oxide vapor film, plasma pretreatment is performed on the surface of a plastic base material such as the second base material 51 before the aluminum oxide vapor deposition step in order to make the transformation rate of the transition region of the aluminum oxide vapor deposition film a preferable value. It is preferable to do. In the plasma pretreatment, the mixing ratio of oxygen gas supplied as plasma gas to argon or helium is 5: 1, preferably 2: 1. By setting the mixing ratio to 5: 1, the film formation energy of the vapor-deposited aluminum on the plastic base material increases, and by further setting it to 2: 1, the formation of aluminum hydroxide is formed near the interface of the base material. That is, the transformation rate of the transition region is reduced.

As a vapor deposition method for forming a vapor deposition film, various vapor deposition methods can be applied from physical vapor deposition and chemical vapor deposition. The physical vapor deposition method can be selected from the group consisting of a vapor deposition method, a sputtering method, an ion plating method, an ion beam assist method, and a cluster ion beam method, and the chemical vapor deposition method includes a plasma CVD method, a plasma polymerization method, and a thermal vapor deposition method. It can be selected from the group consisting of the CVD method and the catalytic reaction type CVD method. In this embodiment, the thin-film deposition method of the physical vapor deposition method is suitable.

The thickness of the aluminum oxide vapor-deposited film formed as described above is preferably 3 nm or more and 50 nm or less, and preferably 8 nm or more and 30 nm or less. Within this range, it is easy to maintain the barrier property.

[Gas barrier coating film]
On the vapor deposition layer 52 such as a transparent vapor deposition layer, the general formula R ¹ _n M (OR ² ) _m (where R ¹ and R ² represent organic groups having 1 to 8 carbon atoms, and M represents an organic group having 1 to 8 carbon atoms. Represents a metal atom, n represents an integer of 0 or more, m represents an integer of 1 or more, and n + m represents the valence of M) and at least one or more alkoxides as described above. A transparent gas barrier that contains a polyvinyl alcohol resin and / or an ethylene / vinyl alcohol copolymer and is polycondensed by the solgel method in the presence of a solgel method catalyst, acid, water, and an organic solvent. A gas barrier coating film obtained by the sex composition may be provided. The gas barrier coating film is preferably transparent.

As the alkoxide represented by the above general formula R ¹ _n M (OR ² ) _m , at least one or more of a partial hydrolyzate of the alkoxide and a condensate of the hydrolysis of the alkoxide can be used. Further, as the partial hydrolyzate of the above alkoxide, it is not necessary that all of the alkoxy groups are hydrolyzed, and one or more of them may be hydrolyzed, or a mixture thereof. As the condensate of hydrolysis of alkoxide, one having a dimer or more of a partially hydrolyzed alkoxide, specifically, one having a dimer of 2 to 6 is used.

In the above-mentioned alkoxide represented by the general formula R ¹ _n M (OR ² ) _m , silicon, zirconium, titanium, aluminum, or the like can be used as the metal atom represented by M. Preferred metals include, for example, silicon, titanium and the like. Further, in the present invention, the alkoxide may be used alone or by mixing alkoxides of two or more different metal atoms in the same solution.

Further, in the alkoxide represented by the above general formula R ¹ _n M (OR ² ) _m , specific examples of the organic group represented by R ¹ include, for example, a methyl group, an ethyl group, an n-propyl group and i. Examples thereof include alkyl groups such as -propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, n-hexyl group, n-octyl group and others. Further, in the alkoxide represented by the above general formula R ¹ _n M (OR ² ) _m , specific examples of the organic group represented by R ² include, for example, a methyl group, an ethyl group, an n-propyl group and i. -Propyl group, n-butyl group, sec-butyl group, etc. can be mentioned. In addition, these alkyl groups may be the same or different in the same molecule.

When preparing the above transparent gas barrier composition, for example, a silane coupling agent or the like may be added. As the above-mentioned silane coupling agent, known organic reactive group-containing organoalkoxysilanes can be used. In particular, organoalkoxysilanes having an epoxy group are preferably used, and specifically, for example, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, or β- (3, 4-Epylcyclohexyl) Ethyltrimethoxysilane and the like can be used. The above-mentioned silane coupling agent may be used alone or in combination of two or more.

The oxygen permeability and the water vapor transmission rate of the laminate 30 provided with the thin-film deposition layer 52 are preferably 2 or less (cc / m ² · day · atm) and 2 or less (g / m ² · day), respectively. The oxygen permeability is measured according to JIS K7126 (isopressure method) using an oxygen barrier measuring instrument OXTRAN manufactured by Mocon, USA under 23 ° C. and 90% RH conditions. The water vapor transmission rate is measured according to JIS K7129 (Method B) using a water vapor barrier measuring instrument PERMATRAN manufactured by Mocon, USA under 40 ° C. and 90% RH conditions.

(Second adhesive layer)
The second adhesive layer 55 contains a second adhesive for adhering the second film 50 and the third film 60. As an example of the second adhesive, an ether-based two-component reaction type adhesive can be mentioned. Examples of the ether-based two-component reaction type adhesive include polyurethane and the like, as in the case of the first adhesive. Polyurethane is a cured product produced by the reaction of a polyol as a main agent and an isocyanate compound as a curing agent. As the polyol, a polyether polyol or a polyester polyol can be used, but it is preferable to use a polyester polyol. Further, as the curing agent, it is preferable to use an aromatic isocyanate compound as in the case of the first adhesive layer 45.

In the second adhesive layer 55, for example, the adhesive composition is applied to the second film 50 or the third film 60, and then the adhesive composition is dried, and the main agent and the solvent in the adhesive composition are used. Is reacted to cure the adhesive composition. The thickness of the second adhesive layer 55 is preferably 1 μm or more, more preferably 2 μm or more.

(Third film)
The third film 60 includes at least the sealant layer 61 constituting the inner surface 30x of the laminated body 30. As a material constituting the sealant layer 61, a resin such as polyethylene can be used.

Polyethylene is classified into, for example, low density polyethylene, medium density polyethylene, and high density polyethylene based on the density. The low-density polyethylene is polyethylene having a density of 0.910 g / cm ³ or more and 0.925 g / cm ³ or less. The medium density polyethylene is polyethylene having a density of 0.926 g / cm ³ or more and 0.940 g / cm ³ or less. The high-density polyethylene is polyethylene having a density of 0.941 g / cm ³ or more and 0.965 g / cm ³ or less. Low-density polyethylene can be obtained, for example, by polymerizing ethylene at a high pressure of 1000 atm or more and less than 2000 atm. Medium-density polyethylene and high-density polyethylene can be obtained, for example, by polymerizing ethylene at medium pressure or low pressure of 1 atm or more and less than 1000 atm. The medium-density polyethylene and the high-density polyethylene may partially contain a copolymer of ethylene and α-olefin.

Even when ethylene is polymerized at medium pressure or low pressure, medium-density or low-density polyethylene can be produced when a copolymer of ethylene and α-olefin is contained. Such polyethylene is referred to as linear low density polyethylene. The linear low-density polyethylene is obtained by copolymerizing an α-olefin with a linear polymer obtained by polymerizing ethylene at medium pressure or low pressure to introduce a short chain branch. Examples of α-olefins include 1-butene (C ₄ ), 1-hexene (C ₆ ), 4-methylpentene (C ₆ ), 1-octene (C ₈ ) and the like. The density of the linear low-density polyethylene is, for example, 0.915 g / cm ³ or more and 0.945 g / cm ³ or less.

As the polyethylene constituting the sealant layer 61, low-density polyethylene, linear low-density polyethylene, or the like can be used. Preferably, the sealant layer 61 contains at least linear low density polyethylene. This makes it possible to increase the sealing strength and the impact resistance of the bag 10 such as drop strength. The sealant layer 61 may further contain low density polyethylene in addition to the linear low density polyethylene. This makes it possible to improve the tearability of the laminated body 30. When the sealant layer 61 contains both the linear low density polyethylene and the low density polyethylene, the content (% by weight) of the linear low density polyethylene is preferably larger than the content (% by weight) of the low density polyethylene. .. The sealant layer 61 may be a single layer or a multilayer.

The thickness of the sealant layer 61 is, for example, 50 μm or more, preferably 60 μm or more, more preferably 70 μm or more, and further preferably 80 μm or more. The thickness of the sealant layer 61 is preferably 160 μm or less, more preferably 130 μm or less.

Layer structure of the lower film Next, the layer structure of the lower film 16 will be described.

The layer structure of the lower film 16 is arbitrary as long as it has an inner surface that can be joined to the inner surface of the front surface film 14 and the inner surface of the back surface film 15. For example, similarly to the front surface film 14 and the back surface film 15, the above-mentioned laminate 30 may be used as the lower film 16. Alternatively, a film having an inner surface composed of a sealant layer and having a structure different from that of the laminated body 30 may be used as the lower film 16. For example, since the lower film 16 is not required to have tearability, the content (% by weight) of the low-density polyethylene in the sealant layer of the lower film 16 is the same as that of the low-density polyethylene in the sealant layer 61 of the front surface film 14 and the back surface film 15. It may be smaller than the content (% by weight). Alternatively, the sealant layer of the lower film 16 may not contain low density polyethylene. The thickness of the sealant layer of the lower film 16 is, for example, 60 μm or more, preferably 70 μm or more, more preferably 80 μm or more, and further preferably 100 μm or more.

Method for manufacturing the first film Next, an example of the method for manufacturing the first film 40 will be described.

First, a resin material containing PBT as a main component is prepared. Subsequently, the resin material is extruded by a melt extrusion method such as a casting method or a tubular method to produce a film-shaped first base material 41. Subsequently, the print layer 42 is formed on the first base material 41. In this way, the first film 40 including the first base material 41 and the printing layer 42 can be obtained.

Method for manufacturing the second film Next, an example of the method for manufacturing the second film 50 will be described.

First, a second base material 51 containing PET as a main component is prepared. Subsequently, a metal such as aluminum, a metal oxide such as aluminum oxide, and an inorganic oxide such as silicon oxide are deposited on the surface of the second base material 51 to form the vapor deposition layer 52. In this way, the second film 50 including the second base material 51 and the vapor deposition layer 52 can be obtained.

Method for Manufacturing Laminated Body Next, an example of a method for manufacturing the laminated body 30 will be described.

First, the above-mentioned first film 40 and second film 50 are prepared. Subsequently, the first film 40 and the second film 50 are laminated via the first adhesive layer 45 by the dry laminating method. Then, by the dry laminating method, the laminated body including the first film 40 and the second film 50 and the third film 60 are laminated via the second adhesive layer 55. Thereby, the laminated body 30 including the first film 40, the second film 50, and the third film 60 can be obtained.

Alternatively, first, the second film 50 and the third film 60 are laminated by a dry laminating method via the second adhesive layer 55, and then the first film 40 and the lamination including the second film 50 and the third film 60 are laminated. The laminated body 30 may be manufactured by laminating the body and the body via the first adhesive layer 45 by a dry laminating method.

In the dry laminating method, first, the adhesive composition is applied to one of the two films to be laminated. Subsequently, the applied adhesive composition is dried to volatilize the solvent. Then, the two films are laminated via the dried adhesive composition. Subsequently, the two laminated films are wound and aged for 24 hours or more in an environment of, for example, 20 ° C. or higher.

Method for manufacturing a bag A front surface film 14 and a back surface film 15 made of the above-mentioned laminate 30 are prepared. Further, the folded lower film 16 is inserted between the front surface film 14 and the back surface film 15. Subsequently, the inner surfaces of the films are heat-sealed to form a sealing portion such as a lower sealing portion 12a, a side sealing portion 13a, and a spout sealing portion 20a. Further, the films bonded to each other by heat sealing are cut into an appropriate shape to obtain the bag 10 shown in FIG.

Subsequently, the plurality of stacked bags 10 are charged into the filling device. In the filling device, the bags 10 are pulled out one by one, and the bags 10 are transported to a place for filling the contents. Next, the contents are filled in the bag 10 through the opening 11b of the upper portion 11. After that, the upper portion 11 is heat-sealed to form an upper seal portion. Subsequently, the bag 10 in which the contents are contained is slid on a transport path having a surface made of metal, and the bag 10 is discharged from the filling device. In this way, the bag 10 in which the contents are contained and sealed can be obtained.

Hereinafter, the advantages of the bag 10 according to the present embodiment will be described.

In the present embodiment, the following effects can be obtained by including the first base material 41 containing PBT as a main component in the laminate 30 constituting the front surface film 14 and the back surface film 15 of the bag 10.
First, PBT is excellent in printability. Therefore, as in the case of polyethylene terephthalate (hereinafter, also referred to as PET), the print layer 42 can be provided on the first base material 41 containing PBT.
In addition, PBT has high strength. Therefore, the piercing strength of the laminated body 30 and the bag 10 can be increased as in the case where the laminated body constituting the bag 10 contains nylon. The piercing strength of the laminated body 30 is preferably 13 N or more, more preferably 15 N or more, and further preferably 17 N or more. The method for measuring the piercing strength will be described in Example A1 described later.

Further, PBT has a characteristic that it is less likely to absorb water than nylon. Therefore, even when the first base material 41 containing PBT is arranged on the outer surface 30y of the laminated body 30, the first base material 41 absorbs moisture and the friction coefficient of the outer surface of the bag 10 increases. It can be suppressed. For example, there is a large difference between the coefficient of friction between the outer surfaces of the bags 10 when placed in a normal temperature environment and the coefficient of friction between the outer surfaces of the bags 10 after being placed in a high temperature and high humidity environment. It can be suppressed from becoming. This makes it possible to efficiently carry out the above-mentioned drawing step and transporting step of the bag 10 in the filling device. After being stored for 48 hours in a high temperature constant temperature bath with a temperature of 40 ° C and a humidity of 90%, and the coefficient of friction between the outer surfaces of the bags 10 when placed in an environment with a temperature of 20 to 30 ° C and a humidity of 40 to 60%. The difference from the coefficient of friction between the outer surfaces of the bags 10 is preferably 0.03 or less.

Further, in the present embodiment, the second film 50 can be provided with a gas barrier property by providing the vapor deposition layer 52 on the second base material 51.

Further, according to the present embodiment, the sealant layer 61 of the laminate 30 constituting the front surface film 14 and the back surface film 15 of the bag 10 contains a polyethylene resin such as linear low-density polyethylene. This makes it possible to increase the sealing strength and the impact resistance of the bag 10 such as drop strength.

It is possible to make various changes to the above-described embodiment. Hereinafter, modification examples will be described with reference to the drawings as necessary. In the following description and the drawings used in the following description, the same reference numerals as those used for the corresponding portions in the above-described embodiment will be used for the portions that can be configured in the same manner as in the above-described embodiment. Duplicate explanations will be omitted. Further, when it is clear that the action and effect obtained in the above-described embodiment can be obtained in the modified example, the description thereof may be omitted.

(Modification example of layer structure)
In the above-described embodiment, the first base material 41 contains 51% by mass or more of PBT, and the second base material 51 contains 51% by mass or more of PET, so that the laminate 30 has puncture resistance and slipperiness. I showed an example to increase. However, the present invention is not limited to this, and the first base material 41 contains 51% by mass or more of PET, and the second base material 51 contains 51% by mass or more of PBT, so that the laminate 30 has puncture resistance and slippage. You may enhance the sex. As the PBT of the second base material 51, the PBT according to the first configuration described in the above-mentioned first base material 41 or the PBT according to the second configuration can be used.

The fact that the second base material 51 contains 51% by mass or more of PBT and the first base material 41 contains 51% by mass or more of PET also contributes to the improvement of the dimensional stability, printability, and slipperiness of the laminate 30. do.

Further, both the first base material 41 and the second base material 51 may contain 51% by mass or more of PBT. As the PBT in this case, the PBT according to the first configuration or the PBT according to the second configuration described in the above-mentioned first base material 41 can be used.

Table 1 summarizes examples of combinations of materials constituting the first base material 41 and the second base material 51. In Table 1, the notation "PBT" means that 51% by mass or more of PBT is contained in the resin constituting the film of the first base material 41 or the second base material 51. Further, in Table 1, the notation "PET" means that 51% by mass or more of PET is contained in the resin constituting the film of the first base material 41 or the second base material 51.

Further, in the above-described embodiment, an example in which the print layer 42 is provided on the inner surface 30x side of the first base material 41 is shown, but the present invention is not limited to this, and the outer surface 30y side of the second base material 51 is not limited thereto. Alternatively, the print layer 42 may be provided on the inner surface 30x side.

Further, in the above-described embodiment, the example in which the vapor deposition layer 52 is provided on the second base material 51 is shown, but the present invention is not limited to this, and the vapor deposition is performed on the inner surface 30x side of the first base material 41. The layer 52 may be provided. Further, the laminated body 30 does not have to include the vapor deposition layer 52.

The following is an example of the arrangement of each layer.
Arrangement Example 1: First base material / first adhesive layer / vapor deposition layer / second base material / second adhesive layer / sealant layer Arrangement example 2: first base material / printing layer / first adhesive layer / vapor deposition Layer / Second Base Material / Second Adhesive Layer / Sealant Layer Arrangement Example 3: First Base Material / First Adhesive Layer / Printing Layer / Vapor Deposition Layer / Second Base Material / Second Adhesive Layer / Sealant Layer Arrangement Example 4: First base material / first adhesive layer / vapor deposition layer / second base material / printing layer / second adhesive layer / sealant layer Arrangement example 5: First base material / first adhesive layer / second Base material / vapor deposition layer / second adhesive layer / sealant layer arrangement example 6: first substrate / printing layer / first adhesive layer / second substrate / vapor deposition layer / second adhesive layer / sealant layer arrangement example 7: First base material / first adhesive layer / printing layer / second base material / vapor deposition layer / second adhesive layer / sealant layer Arrangement example 8: First base material / first adhesive layer / second base Material / vapor deposition layer / printing layer / second adhesive layer / sealant layer arrangement example 9: first substrate / vapor deposition layer / first adhesive layer / second substrate / second adhesive layer / sealant layer arrangement example 10 : 1st base material / vapor deposition layer / printing layer / 1st adhesive layer / 2nd base material / 2nd adhesive layer / sealant layer Arrangement example 11: 1st base material / vapor deposition layer / 1st adhesive layer / printing Layer / Second Base Material / Second Adhesive Layer / Sealant Layer Arrangement Example 12: First Base Material / Vapor Deposition Layer / First Adhesive Layer / Second Base Material / Printing Layer / Second Adhesive Layer / Sealant Layer Arrangement Example 13: First base material / vapor deposition layer / gas barrier coating film / printing layer / first adhesive layer / second substrate / second adhesive layer / sealant layer The vapor deposition layer is on the outer surface side of the printing layer. When arranged, the vapor-deposited layer is a transparent vapor-deposited layer with transparency. The transparent thin-film deposition layer may satisfy both the first preferred form and the second preferred form described above, may satisfy only one of the above forms, or may not satisfy both forms. .. Further, the laminated body in which the vapor-filmed layer is removed from each of the above-mentioned arrangement examples 1 to 13 is also included in the example of the laminated body 30 of the present application.

(Modification example of bag)
In the above-described embodiment, the bag 10 is a gusset-type bag provided with a spout portion 20, but the specific configuration of the bag 10 is not particularly limited. For example, the bag 10 may be a so-called four-sided seal bag formed by joining the inner surfaces of the front surface film 14 and the back surface film 15 made of the laminated body 30 at the upper portion 11, the lower portion 12, and the side portion 13. Further, the bag 10 does not have to be provided with the spout portion 20. For example, the bag 10 may be a gusset-type bag that does not have a spout portion 20 and is configured to be self-supporting.

(Modified example of bag usage)
In the present embodiment described above, an example is shown in which the bag 10 is a refill bag for containing fluid contents such as liquid and powder to be refilled into a bottle. However, the use of the bag 10 is not limited to the refill bag. For example, the user may use the contents contained in the bag 10 as they are without refilling them into bottles or the like.

(Modified example of use of laminated body)
In the above-described embodiment, an example in which the laminate 30 including the first film 40, the second film 50, and the third film 60 is used as a packaging material constituting the front surface film 14 and the back surface film 15 of the bag 10. Indicated. However, the use of the laminated body 30 is not limited to the packaging material for forming the bag. For example, the laminate 30 may be used as a label or sheet material that is not a closed container such as a bag.

Next, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the description of the following Examples as long as the gist of the present invention is not exceeded.

Example A1
A film-shaped first base material 41 containing the plurality of layers 41a described in the first configuration described above and produced by a casting method was prepared. The content of PBT in each layer 41a was 80%, the number of layers of the layer 41a was 1024, and the thickness of the first base material 41 was 15 μm. Subsequently, a print layer 42 was formed on the film-shaped first base material 41 using a finale manufactured by DIC Graphics Corporation. The thickness of the print layer 42 was 1 μm. In this way, the first film 40 including the first base material 41 and the printing layer 42 was produced.

In addition, a second base material 51 containing 100% by mass of PET was prepared. The thickness of the second base material 51 was 12 μm. Subsequently, aluminum was vapor-deposited on the outer surface 30y side of the second base material 51 to form a thin-film deposition layer 52. In this way, the second film 50 including the second base material 51 and the thin-film deposition layer 52 was produced.

Further, a film-like third film 60 including the sealant layer 61 was prepared. As the material constituting the sealant layer 61, a mixture of the following three types of resins in the following weight% was used.
・ Linear low density polyethylene (density: 0.918g / cm ³ , MFR: 3.8) 63.5% by weight
・ Low density polyethylene (density: 0.919g / cm ³ , MFR: 2.0) 35.0% by weight
・ Slip agent masterbatch 1.5% by weight based on low density polyethylene (density: 0.921 g / cm ³ , MFR: 5.4)
MFR means Melt flow rate. The thickness of the sealant layer 61 was 120 μm.

Next, the first film 40 and the second film 50 were laminated by a dry laminating method via the first adhesive layer 45. The adhesive of the first adhesive layer 45 contains Takelac (registered trademark) A-310 manufactured by Mitsui Chemicals, Inc. as a main agent, and Takenate (registered trademark) A-3 manufactured by Mitsui Chemicals, Inc. as a curing agent. I used the one. A-310 contains a polyol. A-3 contains an aromatic isocyanate compound. The thickness of the first adhesive layer 45 was 3 μm.

Next, the laminated body of the first film 40 and the second film 50 and the third film 60 were laminated by a dry laminating method to obtain a laminated body 30. Like the first adhesive layer 45, the second adhesive layer 55 contains Takelac (registered trademark) A-310 manufactured by Mitsui Chemicals, Inc. as a main agent, and Takenate (registered) manufactured by Mitsui Chemicals, Inc. as a curing agent. Trademark) A-3 was used. The thickness of the second adhesive layer 55 was 3 μm. In the laminate 30 thus obtained, the first base material, the printing layer, the first adhesive layer, the thin-film deposition layer, the second base material, the second adhesive layer, and the sealant layer are laminated in this order from the outer surface side. It is a thing.

(Evaluation of piercing strength)
Subsequently, the piercing strength of the laminated body 30 was measured according to JIS Z1707 7.4. As a measuring instrument, a Tensilon universal material tester RTC-1310 manufactured by A & D was used. Specifically, as shown in FIG. 5, a semi-circular needle 70 having a diameter of 1.0 mm and a tip shape radius of 0.5 mm from the outer surface 30y side with respect to the test piece of the laminated body 30 in a fixed state. Was pierced at a speed of 50 mm / min (50 mm per minute), and the maximum value of stress until the needle 70 penetrated the laminate 30 was measured. The maximum value of stress was measured for 5 or more test pieces, and the average value was taken as the piercing strength of the laminated body 30. The environment at the time of measurement was a temperature of 23 ° C. and a relative humidity of 50%. As a result, the piercing strength was 17N.

(Evaluation of slipperiness)
Subsequently, the slipperiness of the outer surface 30y of the laminated body 30 was evaluated. Here, the coefficient of friction of the outer surface 30y of the laminated body 30 was measured. Specifically, the static friction coefficient and the dynamic friction coefficient between the outer surface 30y of the laminated body 30 and the metal surface, and the static friction coefficient and the dynamic friction coefficient between the outer surfaces 30y of the laminated body 30 were measured. The measurement was performed in accordance with JIS K-7125 using a friction measuring instrument TR-2 manufactured by Toyo Seiki Seisakusho Co., Ltd. Aluminum was used as the metal constituting the metal surface.

Hereinafter, a specific method of measurement will be described. In this example, the following first to fourth measurements were carried out.

[First measurement of friction coefficient]
First, the laminated body 30 was cut to prepare a test piece having a width of 70 mm and a length of 152 mm. Subsequently, the test piece is stored in a room at a temperature of 20 to 30 ° C. and a humidity of 40 to 60% for at least 24 hours, and then the test piece is placed on the metal surface so that the outer surface of the test piece is in contact with the metal surface. bottom. Subsequently, a thread containing a member having a width of 63 mm and a length of 63 mm and having a mass of 200 g was placed on the test piece. Subsequently, the test piece was slid on a metal surface at a speed of 100 mm / min. The static friction coefficient and the dynamic friction coefficient of the outer surface of the test piece were calculated based on the force applied to the test piece at the start of sliding and the force applied to the test piece during the activity. As a result, the static friction coefficient and the dynamic friction coefficient were 0.11 and 0.11. The environment at the time of measurement was a standard state specified in JIS K7100, and the temperature was 23 ° C. and the humidity was 50%.
[Second measurement of friction coefficient]
The outer surface of the test piece was stored in a high temperature constant temperature bath at a temperature of 40 ° C. and a humidity of 90% for 48 hours, and then the test piece was placed on a metal surface in the same manner as in the first measurement. The coefficient of static friction and the coefficient of dynamic friction were measured. The measurement was carried out within 5 minutes after the test piece was taken out from the high temperature constant temperature bath. As a result, the static friction coefficient and the dynamic friction coefficient were 0.14 and 0.13.
[Third measurement of friction coefficient]
Two laminates 30 are prepared, and the test piece of one laminate 30 is attached to the other laminate 30 so that the outer surface of the test piece obtained from one laminate 30 is in contact with the outer surface 30y of the other laminate 30. Except for the fact that the test piece was placed, the static friction coefficient and the dynamic friction coefficient of the outer surface of the test piece were measured in the same manner as in the case of the first measurement. As a result, the static friction coefficient (normal temperature static friction coefficient) and the dynamic friction coefficient (normal temperature dynamic friction coefficient) were 0.21 and 0.22.
[Fourth measurement of friction coefficient]
After preparing two laminates 30 and storing the two laminates 30 in a high temperature constant temperature bath at a temperature of 40 ° C. and a humidity of 90% for 48 hours, the outer surface of the test piece of one laminate 30 is exposed to the other laminate 30. The static friction coefficient and the dynamic friction coefficient of the outer surface of the test piece were measured in the same manner as in the case of the first measurement except that the test piece was placed on the outer surface 30y. As a result, the static friction coefficient (high temperature and high humidity static friction coefficient) and the dynamic friction coefficient (high temperature and high humidity dynamic friction coefficient) were 0.24 and 0.24.

Example A2
The first base material 41 of the first film 40 contains 51% by mass of PBT described in the second configuration described above, has a melting point of PBT of 224 ° C., an IV value of 1.26 dl / g, and is tubular. The laminated body 30 was produced in the same manner as in Example A1 except that the single-layer film produced by the method was used. The first base material 41 was a single-layer film composed only of PBT and additives, and the thickness of the first base material 41 was 15 μm.

Subsequently, the piercing strength of the laminated body 30 was measured in the same manner as in the case of Example A1. As a result, the piercing strength was 17N. Further, the friction coefficient of the laminated body 30 was measured in the same manner as in the case of Example A1. The results were as follows.
・ First measurement Static friction coefficient: 0.12 Dynamic friction coefficient: 0.10
・ Second measurement Static friction coefficient: 0.14 Dynamic friction coefficient: 0.13
・ Third measurement Static friction coefficient: 0.20 Dynamic friction coefficient: 0.22
・ Fourth measurement Static friction coefficient: 0.22 Dynamic friction coefficient: 0.22

Example A3
Examples except that the PBT constituting the first substrate 41 of Example A1 was used as the second substrate 51 and the PET constituting the second substrate 51 of Example A1 was used as the first substrate 41. The laminated body 30 was produced in the same manner as in the case of A1.

Subsequently, the piercing strength of the laminated body 30 was measured in the same manner as in the case of Example A1. As a result, the piercing strength was 17N. Further, the friction coefficient of the laminated body 30 was measured in the same manner as in the case of Example A1. The results were as follows.
・ First measurement Static friction coefficient: 0.11 Dynamic friction coefficient: 0.09
・ Second measurement Static friction coefficient: 0.10 Dynamic friction coefficient: 0.10
・ Third measurement Static friction coefficient: 0.18 Dynamic friction coefficient: 0.18
・ Fourth measurement Static friction coefficient: 0.18 Dynamic friction coefficient: 0.17

Comparative Example A1
The laminated body 30 was produced in the same manner as in Example A1 except that a nylon film having a thickness of 15 μm (Bonil W manufactured by Kojin Holdings Co., Ltd.) was used as the first base material 41 of the first film 40. ..

Subsequently, the piercing strength of the laminated body 30 was measured in the same manner as in the case of Example A1. As a result, the piercing strength was 17N. Further, the friction coefficient of the laminated body 30 was measured in the same manner as in the case of Example A1. The results were as follows.
・ First measurement Static friction coefficient: 0.13 Dynamic friction coefficient: 0.13
・ Second measurement Static friction coefficient: 0.16 Dynamic friction coefficient: 0.15
・ Third measurement Static friction coefficient: 0.20 Dynamic friction coefficient: 0.19
・ Fourth measurement Static friction coefficient: 0.27 Dynamic friction coefficient: 0.25

The measurement results of the static friction coefficient μ _S and the dynamic friction coefficient μ _D of the laminates of Examples A1 to A3 and Comparative Example A1 are summarized in FIG. Further, the layer configurations and evaluation results of the laminated bodies of Examples A1 to A3 and Comparative Example A1 are summarized in FIG. 7. In FIG. 7, in the column of "layer structure", the constituent elements of the laminated body excluding the adhesive layer are described from the top in order from the layer on the outer surface side.

As shown in FIG. 6, when the outer surface 30y of the laminated body 30 is made of nylon and the laminated body 30 is exposed to a high humidity environment, the static friction coefficient and the dynamic friction coefficient with respect to the metal surface are 0.15. As described above, the static friction coefficient (high temperature and high humidity static friction coefficient) and the dynamic friction coefficient (high temperature and high humidity dynamic friction coefficient) with respect to the laminated body 30 were 0.25 or more. Regarding the friction coefficient between the outer surfaces of the two laminates, the value obtained by subtracting the normal temperature static friction coefficient from the high temperature and high humidity static friction coefficient is 0.07, and the value obtained by subtracting the normal temperature dynamic friction coefficient from the high temperature and high humidity dynamic friction coefficient is 0.07. It was 0.06.
On the other hand, when the outer surface 30y of the laminated body 30 is composed of PBT or PET, the static friction coefficient and the dynamic friction coefficient with respect to the metal surface are 0 even when the laminated body 30 is exposed to a high humidity environment. It was .14 or less, and the static friction coefficient (high temperature and high humidity and static friction coefficient) and the dynamic friction coefficient (high temperature and high humidity and dynamic friction coefficient) with respect to the laminated body 30 were 0.24 or less. Regarding the friction coefficient between the outer surfaces of the two laminates, the value obtained by subtracting the normal temperature static friction coefficient from the high temperature and high humidity static friction coefficient is 0.03 or less, and the value obtained by subtracting the normal temperature dynamic friction coefficient from the high temperature and high humidity dynamic friction coefficient. Was 0.03 or less, more specifically 0.02 or less. In particular, when the outer surface 30y of the laminated body 30 is made of PET, the static friction coefficient and the dynamic friction coefficient with respect to the metal surface are 0.10 or less even when the laminated body 30 is exposed to a high humidity environment. The static friction coefficient and the dynamic friction coefficient with respect to the laminated body 30 were 0.18 or less.

As can be seen from the comparison between Examples A1 to A3 and Comparative Example A1 in FIG. 7, the first base material 41 or the second base material 51 contains PBT, so that the first base material 41 or the second base material 51 is made of nylon. It was possible to achieve the same piercing strength as in the case of including.

Example B1
As a packaging material (hereinafter, also referred to as a body material) constituting the front surface film 14 and the back surface film 15, a laminate having the following layer structure was prepared.
1st base material / 1st adhesive layer / thin-film deposition layer / 2nd base material / 2nd adhesive layer / sealant layer The 1st base material includes a plurality of layers 41a described in the above-mentioned first configuration. , A PBT film produced by the casting method was used. The content of PBT in each layer 41a was 80%, the number of layers of the layer 41a was 1024, and the thickness of the first base material 41 was 12 μm. As the vapor-deposited layer and the second base material, a PET film having a thickness of 12 μm on which aluminum was vapor-deposited was used. As the sealant layer, a polyethylene film having a thickness of 100 μm containing linear low-density polyethylene was used.

Further, as a packaging material (hereinafter, also referred to as a bottom material) constituting the lower film 16, a laminated body having the following layer structure was prepared.
First base material / first adhesive layer / thin-film deposition layer / second base material / second adhesive layer / sealant layer The first base material is a PBT film having a thickness of 12 μm, which is the same as in the case of the above-mentioned body material. Was used. As the thin-film film and the second base material, a PET film having a thickness of 12 μm on which aluminum was vapor-deposited was used as in the case of the body material described above. Further, as the sealant layer, a polyethylene film having a thickness of 100 μm containing linear low-density polyethylene was used.

Subsequently, the bag 10 was manufactured using the above-mentioned body material and bottom material. Then, water was filled inside the bag 10 as a content, and the upper portion 11 was heat-sealed. As a result, as shown in FIG. 8, a bottom gusset type bag 10 having a sealed upper portion 11 was obtained. At this time, a bag 10 in which the amount of water contained is 200 ml (hereinafter, also referred to as a bag 10 having a first capacity) and a bag 10 in which the amount of water contained is 250 ml (hereinafter, a bag having a second capacity). (Also referred to as 10) were produced. In any type of bag 10, the height S1 of the bag 10 was 180 mm and the width S2 was 130 mm. Further, the height S3 of the folded lower film 16, that is, the height from the lower end portion of the bag 10 to the folded portion 16f was 35 mm.

(Evaluation of normal temperature drop)
Subsequently, for each of the first capacity bag 10 and the second capacity bag 10, the bag 10 is dropped in an environment of room temperature (about 20 ° C.), and the bag 10 is inspected for whether or not the bag is broken at room temperature. An evaluation was carried out. Specifically, a test in which the bag 10 held so that the front surface film 14 and the back surface film 15 were held horizontally was dropped from a height of 1.5 m (hereinafter, also referred to as a horizontal drop test) was repeated 10 times. As a result, no bag breakage occurred in either the first capacity bag 10 or the second capacity bag 10. Further, after the horizontal drop test, a test in which the bag 10 held so that the lower portion 12 is located below is dropped from a height of 1.5 m (hereinafter, also referred to as a vertical drop test) was repeated 10 times. As a result, no bag breakage occurred in either the first capacity bag 10 or the second capacity bag 10.

(Low temperature drop evaluation)
In addition, a low temperature drop evaluation was performed using a sample different from the one used in the normal temperature drop evaluation. In the low temperature drop evaluation, first, each of the first capacity bag 10 and the second capacity bag 10 was cooled to 3 ° C. Subsequently, for each of the first capacity bag 10 and the second capacity bag 10 cooled to 3 ° C., the bag 10 is dropped in an environment of room temperature (about 20 ° C.), and the bag 10 is broken. I checked whether it was. Specifically, the above-mentioned horizontal drop test and vertical drop test were carried out for each of the first capacity bag 10 and the second capacity bag 10 as in the case of the room temperature drop evaluation. As a result, in both the first capacity bag 10 and the second capacity bag 10, no bag breakage occurred in the horizontal drop test and the vertical drop test.

Example B2
A laminate constituting the body material was prepared in the same manner as in the case of Example B1 except that the thickness of the sealant layer was 90 μm. Further, the same bottom material as in the case of Example B1 was prepared. Subsequently, in the same manner as in the case of Example B1, the bag 10 is made using the body material and the bottom material, water is filled inside the bag 10 as the contents, and the upper portion 11 is heat-sealed to obtain the first bag. A capacity bag 10 and a second capacity bag 10 were produced.

Subsequently, in the same manner as in Example B1, a room temperature drop evaluation including a horizontal drop test and a vertical drop test was performed. As a result, in both the first capacity bag 10 and the second capacity bag 10, no bag breakage occurred in the horizontal drop test and the vertical drop test.

Moreover, the low temperature drop evaluation including the horizontal drop test and the vertical drop test was carried out in the same manner as in the case of Example B1. As a result, in both the first capacity bag 10 and the second capacity bag 10, no bag breakage occurred in the horizontal drop test and the vertical drop test.

Example B3
A laminate constituting the body material was prepared in the same manner as in the case of Example B1 except that the thickness of the sealant layer was set to 80 μm. Further, the same bottom material as in the case of Example B1 was prepared. Subsequently, in the same manner as in the case of Example B1, the bag 10 is made using the body material and the bottom material, water is filled inside the bag 10 as the contents, and the upper portion 11 is heat-sealed to obtain the first bag. A capacity bag 10 and a second capacity bag 10 were produced.

Subsequently, in the same manner as in Example B1, a room temperature drop evaluation including a horizontal drop test and a vertical drop test was performed. As a result, in both the first capacity bag 10 and the second capacity bag 10, no bag breakage occurred in the horizontal drop test and the vertical drop test.

Moreover, the low temperature drop evaluation including the horizontal drop test and the vertical drop test was carried out in the same manner as in the case of Example B1. As a result, in both the first capacity bag 10 and the second capacity bag 10, no bag breakage occurred in the horizontal drop test and the vertical drop test.

Example B4
A laminate constituting the body material was prepared in the same manner as in the case of Example B1 except that the thickness of the sealant layer was 70 μm. Further, the same bottom material as in the case of Example B1 was prepared. Subsequently, in the same manner as in the case of Example B1, the bag 10 is made using the body material and the bottom material, water is filled inside the bag 10 as the contents, and the upper portion 11 is heat-sealed to obtain the first bag. A capacity bag 10 and a second capacity bag 10 were produced.

Subsequently, in the same manner as in Example B1, a room temperature drop evaluation including a horizontal drop test and a vertical drop test was performed. As a result, in the bag 10 having the first capacity, no bag breakage occurred in the horizontal drop test and the vertical drop test. On the other hand, in the bag 10 having the second capacity, the bag was not broken in the horizontal drop test, but the bag was broken in the vertical drop test.

Moreover, the low temperature drop evaluation including the horizontal drop test and the vertical drop test was carried out in the same manner as in the case of Example B1. As a result, neither the first capacity bag 10 nor the second capacity bag 10 had a bag breakage in the horizontal drop test, but a bag breakage occurred in the vertical drop test.

Example B5
A laminate constituting the body material was prepared in the same manner as in the case of Example B1 except that the thickness of the sealant layer was set to 60 μm. Further, the same bottom material as in the case of Example B1 was prepared. Subsequently, in the same manner as in the case of Example B1, the bag 10 is made using the body material and the bottom material, water is filled inside the bag 10 as the contents, and the upper portion 11 is heat-sealed to obtain the first bag. A capacity bag 10 and a second capacity bag 10 were produced.

Subsequently, in the same manner as in Example B1, a room temperature drop evaluation including a horizontal drop test and a vertical drop test was performed. As a result, neither the first capacity bag 10 nor the second capacity bag 10 had a bag breakage in the horizontal drop test, but a bag breakage occurred in the vertical drop test.

Moreover, the low temperature drop evaluation including the horizontal drop test and the vertical drop test was carried out in the same manner as in the case of Example B1. As a result, in the bag 10 of the first capacity, the bag was not broken in the horizontal drop test, but the bag was broken in the vertical drop test. In the bag 10 of the second capacity, the bag was broken in the horizontal drop test and the vertical drop test.

Example B6
A laminate constituting the body material was prepared in the same manner as in the case of Example B1 except that the thickness of the sealant layer was 50 μm. Further, the same bottom material as in the case of Example B1 was prepared. Subsequently, in the same manner as in the case of Example B1, the bag 10 is made using the body material and the bottom material, water is filled inside the bag 10 as the contents, and the upper portion 11 is heat-sealed to obtain the first bag. A capacity bag 10 and a second capacity bag 10 were produced.

Subsequently, in the same manner as in Example B1, a room temperature drop evaluation including a horizontal drop test and a vertical drop test was performed. As a result, neither the first capacity bag 10 nor the second capacity bag 10 had a bag breakage in the horizontal drop test, but a bag breakage occurred in the vertical drop test.

Moreover, the low temperature drop evaluation including the horizontal drop test and the vertical drop test was carried out in the same manner as in the case of Example B1. As a result, in both the first capacity bag 10 and the second capacity bag 10, bag breakage occurred in the horizontal drop test and the vertical drop test.

Example B7
A laminate constituting the body material was prepared in the same manner as in the case of Example B1 except that the thickness of the sealant layer was set to 30 μm. Further, the same bottom material as in the case of Example B1 was prepared. Subsequently, in the same manner as in the case of Example B1, the bag 10 is made using the body material and the bottom material, water is filled inside the bag 10 as the contents, and the upper portion 11 is heat-sealed to obtain the first bag. A capacity bag 10 and a second capacity bag 10 were produced.

Subsequently, in the same manner as in Example B1, a room temperature drop evaluation including a horizontal drop test and a vertical drop test was performed. As a result, in the bag 10 of the first capacity, the bag was not broken in the horizontal drop test, but the bag was broken in the vertical drop test. In the bag 10 of the second capacity, the bag was broken in the horizontal drop test and the vertical drop test.

Moreover, the low temperature drop evaluation including the horizontal drop test and the vertical drop test was carried out in the same manner as in the case of Example B1. As a result, in both the first capacity bag 10 and the second capacity bag 10, bag breakage occurred in the horizontal drop test and the vertical drop test.

The results of the normal temperature drop evaluation and the low temperature drop evaluation of Examples B1 to B7 when the bag 10 having the first capacity is used are summarized in FIG. 9. Further, the results of the normal temperature drop evaluation and the low temperature drop evaluation of Examples B1 to B7 when the second capacity bag 10 is used are summarized in FIG. 10. In FIGS. 9 and 10, "OK" means that the bag 10 did not break after repeating the drop 10 times. Further, "NG" means that the bag 10 was broken during or after the fall was repeated 10 times.

When 200 ml of water is contained in the bag 10, as shown in FIG. 9, the bag 10 is manufactured using a body material containing a sealant layer having a thickness of 30 μm or more, whereby a horizontal drop for evaluation of normal temperature drop is performed. It was possible to suppress the occurrence of bag breakage in the test. Further, by producing the bag 10 using the body material containing the sealant layer having a thickness of 70 μm or more, it was possible to suppress the occurrence of bag breakage in the vertical drop test for normal temperature drop evaluation. Further, by producing the bag 10 using the body material containing the sealant layer having a thickness of 50 μm or more, it was possible to suppress the occurrence of bag breakage in the horizontal drop test for low temperature drop evaluation. Further, by producing the bag 10 using the body material containing the sealant layer having a thickness of 80 μm or more, it was possible to suppress the occurrence of bag breakage in the vertical drop test for low temperature drop evaluation.

When 250 ml of water is contained in the bag 10, as shown in FIG. 10, the bag 10 is manufactured using a body material containing a sealant layer having a thickness of 60 μm or more, whereby a horizontal drop for evaluation of normal temperature drop is performed. It was possible to suppress the occurrence of bag breakage in the test. Further, by producing the bag 10 using the body material containing the sealant layer having a thickness of 80 μm or more, it was possible to suppress the occurrence of bag breakage in the vertical drop test for normal temperature drop evaluation. Further, by producing the bag 10 using the body material containing the sealant layer having a thickness of 70 μm or more, it was possible to suppress the occurrence of bag breakage in the horizontal drop test for low temperature drop evaluation. Further, by producing the bag 10 using the body material containing the sealant layer having a thickness of 80 μm or more, it was possible to suppress the occurrence of bag breakage in the vertical drop test for low temperature drop evaluation.

Example C1
A film-shaped first base material 41 containing the plurality of layers 41a described in the first configuration described above and produced by a casting method was prepared. The content of PBT in each layer 41a was 80%, the number of layers of the layer 41a was 1024, and the thickness of the first base material 41 was 12 μm. Subsequently, while the first base material 41 was wound around a pretreatment drum and conveyed at a transport speed of 400 m / min, plasma pretreatment for introducing plasma from a plasma supply nozzle was performed on the surface of the first base material 41. The conditions for plasma pretreatment are as follows.
・ Plasma intensity: 150 W ・ sec / m ²
-Plasma forming gas: Argon 1200 (sccm), Oxygen 3000 (sccm)
・ Voltage applied between pretreatment drum and plasma supply nozzle: 340V
-Vacuum degree around the pretreatment drum: 3.8 Pa

Subsequently, in the film forming chamber adjacent to the pretreatment chamber where the pretreatment drum is located, an aluminum oxide vapor deposition film having a thickness of 12 nm is formed on the surface of the first substrate 41 subjected to plasma pretreatment by a vacuum vapor deposition method. bottom. The film forming conditions are as follows.
・ Vacuum degree: 8.1 × 10 ^-2 Pa
・ Transport speed: 400m / min
The transmittance of light rays having a wavelength of 366 nm in the obtained aluminum oxide vapor-deposited film was 92%.

Subsequently, a barrier coating agent was coated on the aluminum oxide vapor-deposited film by a spin coating method. Then, it was heat-treated in an oven at 180 ° C. for 60 seconds to form a transparent gas barrier coating film having a thickness of about 400 nm on the aluminum oxide vapor-deposited film. In this way, a first film 40 having a first base material 41 provided with a transparent thin-film deposition layer and a gas barrier coating film was obtained.

The procedure for preparing the barrier coating agent is as follows. First, 385 g of water, 67 g of isopropyl alcohol and 9.1 g of 0.5N hydrochloric acid were mixed, and 175 g of tetraethoxysilane and 9.2 g of glycidoxypropyltrimethoxysilane were cooled to 10 ° C. in a solution adjusted to pH 2.2. Solution A was prepared by mixing while mixing. Further, a solution B was prepared by mixing 14.7 g of polyvinyl alcohol having a degree of polymerization of 2400 having a degree of polymerization of 99% or more, 324 g of water, and 17 g of isopropyl alcohol. The solution obtained by mixing the solution A and the solution B so as to have a weight ratio of 6.5: 3.5 was used as a barrier coating agent.

Subsequently, in the same manner as in the case of Example A1, the first film 40, the second film 50, and the third film 60 were laminated by the dry laminating method to obtain a laminated body 30. Since the laminated body 30 has a transparent thin-film deposition layer and a gas barrier coating film, the gas barrier property of the laminated body 30 can be enhanced.

10 Bag 11 Upper 12 Lower 12a Lower seal 13 Side 13a Side seal 14 Front film 15 Back film 16 Lower film 17 Main body 20 Spout 20a Spout seal 25 Easy-to-open means 26 Notch 30 Laminated body 40 1st film 41 1st base material 41a layer 42 printing layer 45 1st adhesive layer 50 2nd film 51 2nd base material 52 vapor deposition layer 55 2nd adhesive layer 60 3rd film 61 sealant layer

Claims (13)

A laminated body including an outer surface and an inner surface,
The first base material, the first adhesive layer, the second base material, the second adhesive layer, and the sealant layer are provided at least in this order.
The first base material constitutes the outer surface, and the first base material constitutes the outer surface.
The sealant layer constitutes the inner surface, and the sealant layer constitutes the inner surface.
The first substrate contains 51% by mass or more of polyethylene terephthalate or 51% by mass or more of polybutylene terephthalate.
When the first base material contains 51% by mass or more of polyethylene terephthalate, the second base material contains 51% by mass or more of polybutylene terephthalate .
When the first base material contains 51% by mass or more of polybutylene terephthalate, the second base material contains 51% by mass or more of polyethylene terephthalate.
A laminated body having a thickness of the sealant layer of 70 μm or more . The laminate according to claim 1, further comprising a thin-film deposition layer located at least between the first base material and the second base material or between the second base material and the sealant layer. The laminate according to claim 2, further comprising a gas barrier coating film located on the vapor-deposited layer. The laminate according to any one of claims 1 to 3, further comprising a printing layer located between the first base material and the second base material. The laminate according to any one of claims 1 to 4, wherein the sealant layer contains linear low-density polyethylene. The laminate according to any one of claims 1 to 5, wherein the puncture strength of the laminate is 13 N or more. The coefficient of static friction of the outer surface of one of the laminates with respect to the outer surface of the other laminate, which is measured after preparing two of the laminates and storing them in a high temperature constant temperature bath at a temperature of 40 ° C. and a humidity of 90% for 48 hours. The laminated body according to any one of claims 1 to 6, wherein the dynamic friction coefficient is 0.24 or less. Two of the laminates are prepared and stored in an environment with a temperature of 20 to 30 ° C. and a humidity of 40 to 60% for at least 24 hours, and then measured after the outer surface of one of the laminates and the outer surface of the other laminate. The coefficient of static friction and the coefficient of dynamic friction are referred to as the coefficient of static friction at room temperature and the coefficient of dynamic friction at room temperature.
After measuring the room temperature static friction coefficient and the room temperature dynamic friction coefficient, the two layers are stored in a high temperature constant temperature bath at a temperature of 40 ° C. and a humidity of 90% for 48 hours, and then measured on the outer surface of one of the layers and on the other side. When the static friction coefficient and the dynamic friction coefficient with respect to the outer surface of the laminated body are referred to as a high temperature and high humidity static friction coefficient and a high temperature and high humidity dynamic friction coefficient,
Claimed that the value obtained by subtracting the normal temperature static friction coefficient from the high temperature and high humidity static friction coefficient is 0.03 or less, and the value obtained by subtracting the normal temperature dynamic friction coefficient from the high temperature and high humidity dynamic friction coefficient is 0.03 or less. The laminate according to any one of 1 to 7. The laminate according to any one of claims 1 to 8, wherein the base material containing polybutyre terephthalate among the first base material and the second base material has a multilayer structure portion including 10 or more layers. body. Of the first base material and the second base material, the base material containing polybutyre terephthalate has a single-layer structure, and the IV value of polybutyre terephthalate is 1.10 dl / g or more and 1. The laminate according to any one of claims 1 to 8, which is 35 dl / g or less. The first substrate contains polybutylene terephthalate and contains.
The laminate according to any one of claims 1 to 10, wherein the second base material contains polyethylene terephthalate. The first substrate contains polyethylene terephthalate and contains
The laminate according to any one of claims 1 to 10, wherein the second base material contains polybutylene terephthalate. A bag having a main body and a spout connected to the main body.
The laminate according to any one of claims 1 to 12, and the laminate.
A bag comprising a sealing portion for joining the inner surfaces of the laminated body to each other.

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